C210 pilot has near midair collision during entry into traffic pattern at S67.

Attributes
ACN	715404
Time
Date	200611
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : s67.airport
State Reference	ID
Altitude	msl single value : 3500
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Operator	general aviation : personal
Make Model Name	Cessna 210 Centurion / Turbo Centurion 210C 210D
Operating Under FAR Part	Part 91
Flight Phase	descent : approach
Route In Use	approach : traffic pattern
Flight Plan	VFR
Aircraft 2
Operator	general aviation : personal
Make Model Name	Small Aircraft High Wing 1 Eng Fixed Gear
Operating Under FAR Part	Part 91
Flight Phase	descent : approach
Route In Use	approach : traffic pattern
Flight Plan	None
Person 1
Affiliation	other
Function	flight crew : single pilot
Qualification	pilot : commercial
Experience	flight time last 90 days : 150 flight time total : 850 flight time type : 150
ASRS Report	175404
Person 2
Affiliation	other
Function	flight crew : single pilot
Events
Anomaly	conflict : nmac non adherence : far non adherence : published procedure other spatial deviation
Independent Detector	other flight crewa
Miss Distance	horizontal : 200 vertical : 50
Supplementary
Problem Areas	Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance

Narrative:

Aircraft #1 was entering left downwind leg for runway 11 at S67 airport. Started announcing position; intentions; altitude MSL about 12.5 NM north of field. Heard no one talking on frequency. Announced at 10; 7.5; and 2.5 mi out (a habit I have). Heard no one on frequency. Announced a mid field 45 degree entry and noticed an aircraft on downwind; about approach end of downwind. Thought it strange he was not responding on frequency. Announced I would enter in behind that aircraft. While turning from my 45 degree to downwind; was able to see clearly to my left and noticed #2 aircraft near and above my altitude. I had cut that aircraft off when entering pattern. I wondered why 2 aircraft not communicating on frequency. Doublechked my radio; found I had dialed in 122.8. Should have been 122.7. Reset and announced a go around. Seems the #2 aircraft may never have seen me. I do not know this for a fact. Listening in and talking on 122.7; I never heard anyone say anything about it. Could be they were just kind; or as mentioned above; he never saw me.

Original NASA ASRS Text

Title: C210 PLT HAS NMAC DURING ENTRY INTO TFC PATTERN AT S67.

Narrative: ACFT #1 WAS ENTERING L DOWNWIND LEG FOR RWY 11 AT S67 ARPT. STARTED ANNOUNCING POS; INTENTIONS; ALT MSL ABOUT 12.5 NM N OF FIELD. HEARD NO ONE TALKING ON FREQ. ANNOUNCED AT 10; 7.5; AND 2.5 MI OUT (A HABIT I HAVE). HEARD NO ONE ON FREQ. ANNOUNCED A MID FIELD 45 DEG ENTRY AND NOTICED AN ACFT ON DOWNWIND; ABOUT APCH END OF DOWNWIND. THOUGHT IT STRANGE HE WAS NOT RESPONDING ON FREQ. ANNOUNCED I WOULD ENTER IN BEHIND THAT ACFT. WHILE TURNING FROM MY 45 DEG TO DOWNWIND; WAS ABLE TO SEE CLRLY TO MY L AND NOTICED #2 ACFT NEAR AND ABOVE MY ALT. I HAD CUT THAT ACFT OFF WHEN ENTERING PATTERN. I WONDERED WHY 2 ACFT NOT COMMUNICATING ON FREQ. DOUBLECHKED MY RADIO; FOUND I HAD DIALED IN 122.8. SHOULD HAVE BEEN 122.7. RESET AND ANNOUNCED A GAR. SEEMS THE #2 ACFT MAY NEVER HAVE SEEN ME. I DO NOT KNOW THIS FOR A FACT. LISTENING IN AND TALKING ON 122.7; I NEVER HEARD ANYONE SAY ANYTHING ABOUT IT. COULD BE THEY WERE JUST KIND; OR AS MENTIONED ABOVE; HE NEVER SAW ME.

Data retrieved from NASA's ASRS site as of January 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.